MD Consult states that the most common reason people experience thickening of the colon wall is diverticulitis. However, edema, congestive heart failure, cirrhosis of the liver, infections, parasitic infestations and inflammation can also cause intestinal thickening.
MD Consult explains that when the colon exhibits short sections of thickening, the cause is often some type of colon cancer. By contrast, inflammatory diseases usually cause long sections of the intestines to thicken. According to the Mayo Clinic, a common cause of intestinal thickening is Crohn’s diease. Patients with Crohn’s disease or inflammatory bowel diseases often develop scar tissue inside the intestines, which cause the walls to thicken.
The National Center for Biotechnology Information states that thickening of the colon is often observed during a CT scan for some other purpose. In a controlled study, approximately 40 percent of the participants were eventually diagnosed with some type of cancer after scheduling a follow-up colonoscopy. However, 28 percent of those who underwent the colonoscopy following the finding of a thickened colon did not have any significant disease.
LiveScience.com explains that people suffering from thickened colon walls may eventually experience a narrowing of the colon. When this condition, called a stricture, occurs, it can prevent the normal progression of feces through the intestine. If this happens, the intestine may form tunnels that connect with the skin or other organs. Such tunnels are called fistulas.